What type of energy holds molecules together to form matter?

Everything that we see around us -- plants, water, animals, metals, etc. -- is all matter; that is, they occupy space and have mass. The matter is composed of molecules and these molecules are held together by forces known as intermolecular forces. These forces are attractive in nature and can be any of the following:

1. Dipole-dipole forces


2. London dispersion forces


3. hydrogen bonding forces


4. induced dipole forces 

A great example of hydrogen bonding holding molecules together...

Everything that we see around us -- plants, water, animals, metals, etc. -- is all matter; that is, they occupy space and have mass. The matter is composed of molecules and these molecules are held together by forces known as intermolecular forces. These forces are attractive in nature and can be any of the following:

1. Dipole-dipole forces


2. London dispersion forces


3. hydrogen bonding forces


4. induced dipole forces 

A great example of hydrogen bonding holding molecules together to form matter is water. Each water molecule contains an oxygen atom (with partial negative charge) and two hydrogen atoms (with a partial positive charge on each). Each of these atoms is attracted to an oppositely-charged atom of a neighboring water molecule, overall forming four hydrogen bonds with neighboring water molecules. All these molecules held together is what we see as water. 

Interestingly, depending on the magnitude of these intermolecular forces and the kinetic energy of the molecules, the matter may be solid, liquid or gas. For example, if the intermolecular forces between the molecules are strong enough to overcome the kinetic energy of the molecules, the matter will likely be a liquid or a solid.

Hope this helps.